The correct answer is C. Trees provide oxygen for humans, so by reducing trees you reduce oxygen available for humans.
So, we need to know the concept of saturated and unsaturated
Unsaturated fatty acids have one or more double/triple bonds and can absorb more hydrogen atoms.
Saturated fatty acids do not have the above-mentioned properties
The difference between soaps made from vegetable oils and from animal fats are that:
Vegetable oil is unsaturated and therefore the soap is liquid
Animal fats are saturated and therefore the soap is more solid
during an ice age mostly the earths oceans freeze
